Microtia and Complex Congenital Ear Deformities
Microtia is a condition in which the external ear is smaller than normal size and not fully formed. This condition can range from a mild deformity that is not very noticeable, to a major defect called anotia where the external ear is completely missing. The child may have a narrow or missing ear canal, which can affect their ability to hear. Atresia is the absence of underdevelopment of the ear canal and middle ear structures. Atresia is often present with microtia because the outer and middle ear develop at the same time in the fetus. Most children will only have one ear affected, but it is possible for the condition to occur for both ears.
With microtia, the ear is small and not fully formed.
With anotia, the external ear is missing completely.
Images courtesy of the Centers for Disease Control and Prevention, National Center on Birth Defects and Developmental Disabilities.
Diagnosis of Microtia and Anotia
Deformities of the ear are visible at birth and occur in roughly 1 out of every 10,000 babies. Microtia occurs more often in Asians, Hispanics, and Caucasians. It occurs equally among male and female infants.
The Craniofacial specialists team at Hasbro Children’s Hospital will evaluate and manage your child’s condition to optimize their outcome and minimize any complications.
A pediatric otolaryngologist (ear, nose, and throat specialist) will evaluate your baby’s ear function and hearing. Hearing loss in even one ear may affect how your baby learns to talk and may lead to learning difficulties. If your baby has a narrow ear canal, ear wax may build up and need to be removed. Your child may need ear tubes to relieve pressure and help air flow in the ear canal to prevent infections.
Surgery can used to repair an ear with microtia.
A pediatric plastic surgeon will evaluate and diagnose the ear deformity of your child.
The Four Types of Microtia
Grade I: A small ear shaped much like a normal ear but with a small, narrow ear canal.
Grade II: A partial ear is seen at the skin level without a visible ear canal.
Grade III: Absence of most of the ear structure with only a small amount of tissue at the skin level. There is no visible ear canal. This is the most common type of microtia.
Grade IV: The complete absence of the external ear and middle ear structures which is called “atresia."
As your baby grows older and starts to talk, your baby will be closely monitored for language and developmental delays. A Speech Pathologist will evaluate your child and may recommend treatment for kids with speech or language disorders.
Your child may be referred to a Pediatric Geneticist if your baby is identified to have other physical abnormalities. Parents who have a child with microtia have an increased risk of having other children with microtia. When a child with microtia becomes an adult, their children are also at risk of having a child with microtia.
Your doctors will order a hearing test and may order X-rays (CT scan) of the head which provides more information on the structures of the ear. Your doctors may also recommend an ultrasound to check for birth defects of the kidneys and urinary tract, because they develop at the same time as the ear while your baby is in the womb.
Why Does Anotia or Microtia Occur?
Both conditions occur very early in pregnancy. Most of the time, the cause is unknown and there is nothing that could have been done to prevent it. The medication isotretinoin (Accutane) is known to lead to birth defects which include ear deformities. They are also thought to be caused by a combination of genes and other factors that the baby may be exposed to in utero.
The following conditions may increase the risk for microtia:
- A condition of diabetes, prior to pregnancy
- A diet of less than the recommended amounts of carbohydrates and folic acid
Treatment for babies with microtia or anotia depends on the severity of the ear deformity. Your pediatric otolaryngologist will test your baby’s hearing and if there is hearing loss, hearing aids may be recommended. Hearing aids will help with your child’s speech development. Often a bone-anchored hearing aid (BAHA) is offered to restore normal hearing in the affected ear when the cochlear function is normal.
Surgery is performed to reconstruct the external ear to create a normally appearing ear. Surgery is typically performed between 10 and 12 years of age. Reconstructed ears last for your child’s entire life. Children with microtia can play contact sports and enjoy other activities without any extra protection.
The surgeons at Hasbro Children’s Hospital offer different options for reconstruction of an abnormal ear.
There are 3 surgical approaches, and your surgeon will discuss the best option for your child.
Reconstruction of the ear with a Medpor implant placed under the skin. Your child’s pediatric plastic surgeon uses a manmade framework (also called an implant) and your child’s body tissue to create an ear. If your child has microtia on one side, the framework is made to match the healthy ear. The new ear is made so it fits your child as he grows. This is usually a one surgery operation.
Autologous ear reconstruction using rib cartilage. This option typically involves two surgeries to create the new ear. Your surgeon removes cartilage from your child’s rib and uses it to carve a new ear. The cartilage is a flexible and is used to create a frame to build the rest of the ear. This surgery uses your baby’s own tissue so if the new ear is ever injured, it heals just like a natural ear. The reconstructed ear may not look exactly like your baby’s other ear, but it helps even out the appearance and allows children to wear glasses if needed.
An ear prosthesis is also called an artificial ear. These are manmade ears that are more commonly used in adults who develop hearing loss. They are not usually a good choice for young children because they’re costly, fragile and need regular upkeep in order to work well.
Microtia and Anotia Resources for Families